Nasal filter



SePt- 7, 1948- c. l.. Mcc-sovNEY` 2,448,724

v msm. FILTER Filed April 2, 194e Clarence' LJGQvneg nvanbor PatentedSept. "7, i948 UNITED STATES PATENT OFFICE s Claims.

This invention relates to a nasal filter adapted to be placed insideeach nostril of the person using same, and adapted to remove pollen anddust particles from inhaled air, to give relief to persons sufferingfrom hay fever, asthma and other allergies and to filter air for personswho work in atmospheres containing fine irritating particles.

Heretofore, a number of diiierent types of nasal filters have beensuggested, and some have even reached the stage ci commercial use, butthese prior art filters all have one or more disadvantageous features.For instance those made oi metal are generally so hard and rigid thatsubstantial injury to the nose results in case of accidental bumps onthe nose, and frequently such metal lters cause irritation of the skinor inner membrane of the nose coming in contact therewith. Some nasalfilters have been made of plastic materials, but generally suchmaterials are too rigid to Conform themselves to the inner contour ofthe nostril, and therefore either do not obtain a tight t or else causeirritation.

Another diculty is that some prior art nasal lters have used cottonpads, but when cotton becomes moist it wads up very easily and makesbreathing diicult. Sometimes an oil such ,as a pine oil or a heavymineral oil is supplied to the cotton, but such an oil would causesoftening and deterioration of most non-metallic materials from which anasal filter might be made.

The present invention solves the above mentioned and other difficultiesof the prior artby providing a nasal filter of special design and madeoi moulded flexible and at least substantially elastic oil resistantcomposition which can vbe compounded in any desired color shade to matchthe iiesh color of the nose of the person using same. Inside thisflexible nasal iilter there is placed a loose pad or wad of suitableltering aid which is preferably lambs wool coated with a thin lm ofpetrolatum.

The preferred material for making the nasal lter of this invention isvulcanized synthetic rubber of the GR-N type, which is ordinarily madeby emulsion polymerization of butadiene containing about 20 to 40%,ordinarily about 25 to 35% by Weight of acrylonitrile. Other types ofoil-resistant synthetic rubber may be used such as neoprene which is apolymerized chlorprene, or other types of products such as `an organicpclysulde synthetic rubber. Vulcanized natural rubber may be usedalthough it is not as satis-` factory because it tends to soften whencontacted u2 for any substantial length oi time with a material such aspetrolatum.

In making the synthetic rubber composition to be used according to thisinvention, various conventional compounding ingredients may be used ifdesired, such as zinc oxide, clay, various pigments such as white, red,brown, and other pigments, or oil-soluble dyes, waxes, non-volatileoils, curing agents such as sulfur and sulfuryielding compounds, as wellas various accelerators, anti-oxidants, etc.

The following formula is an example of the composition which has beenfound very suitable:

Synthetic rubber1 (non-staining) 100 Zinc oxide 5 Stearic acid Sulfur v2Benzothiazyldisulde 1 Titanium dioxide Wax 2 Du Pont orange OR #6 2 .3

1 Butadiene-acrylonitrile containing 26% acrylonitrile.

2 'lhis may be replaced by .25 part of Du Ponts Orange F to give closerto a flesh color.

The filtering materials used inside the nasal lter of this invention, ispreferably coil lambs wool which has been coated with a thin lmY ofpetrolatum, such as by dipping the wool into a solution of about 1 to10% by weight of petrolatum in a suitable volatile solvent such as apetro.`

leum naphtha, and then allowing the solvent to evaporate. This leaves noodor but gives each fibre a thin coat of petrolatum, which is a solventfor protein, and for Vsome types of dust and'other particles, and issticky enough to mechanically catch and retain even insoluble dustl orother particles which might otherwise irritate the nasal passages.Instead of lambs Wool, other materials may beused such as vvery fineglass wool.` Instead of petrolatum, other adhesive `coating materials`may be used such as water-insoluble polymers, e. g. polybutene of about10,000 to 50,000 mol. wt.

The construction and design of a preferred modification, vand severalalternative modificationsof the nasal filterof this invention willnow bedescribed, in connection with the accompanying drawing in which Fig. 1shows a top View of a nasal filter for boththe left and the rightnostril,

Fig. 2 shows a side elevation of one of the nasal lters, Fig. 3 shows anend View, Fig. 4, a top View of analternative modication, and Fig. 5, aside elevation of a ltering material pad suitablefor insertion into thenasal filter. In all gures, like parts are represented by like numerals,and the scale used is about two times the actual dimensions.

In Fig. 1, the left nasal filter I and the right nasal lter 2 are shownas having a substantially straight inner side wall 3 and curved outerside wall 4, the top surface itself having a number of cross-hatchopenings 5 therein, which are preferably cut at an angle of about. 30 tothe upper horizontal edge of the straight inner side wall 3. The thinbars 6 left in between the cross-hatch openings 5 impart a veryresilient and flexible construction to the nasal lter and adapted tomake a close fit in nostrils of even Widely varying inside contours. Inpreparing one model vof the invention made in actual size, and which hasgiven satisfactory results in service, the curvature of the outer sideWall 4 has been made to correspond to an arc cia circle having a radiusof 11/4 inch. The front end 1 is preferably roundedwith a relativelynarrowcurvature, such as an arc having a radius ofv 0732 inch. The rearportion 8y should have wider curvature such as an 4arc having a radiusoff/32 inch. These two suggested curvatures for the ends 'l and 8 aresubstantially thosewhichl should'be used when the entire nasal=filterhas a length of about` 2%2 inch.- This leaves a longitudinal distance of17/32 inch 'between the centers of the arcs of the ends 1- and. it willbe understood that itis desirable to have nasal filters of variouslengths as people differ yconsiderably in the inner dimensions of thenostrils, and accordingly it is suggested that when these filters aremade in larger -or smaller sizes than the one specifically suggestedabove.

having an overall length of 2%2 inch,` a suitable ratio for constructingthe steel mould in which these synthetic rubber filters are. moulded andcured, is:

radius of small. arcat front/distance between centers ofend arcs/radiusof large arcat back=.12/.65/.23.

Referring to Fig. 2 it is seenthat the upperk corners of the ends 1 and.8 are preferably rounded, as `with an arc of a faginch radius, both.

for ease of. inserting the nasal. lter in proper positionfin thenostril, .andalso for comfort4 by avoiding any sharp corners which mightirritate theV inner part of the nostril. On the other hand the loweredge ofthe ends l and 8 need not. be rounded, and lpreferably are not.The inside edgeI of the lter may be substantially parallel with'theouter edge along the topA andl all of the sides except that near Ythebase there should be afilter `massretaining ridge 9.' This shouldextend-into the interior atleast about7 e inch, and preferably slightlymore such as le inch beyond the inside of the filter walls, which per semay have a thickness of about e inch vto 11e inch, depending partly uponthe overall'size of the lter and upon the resiliency of the syntheticrubber composition used. The lter mass retaining ridge 9 should belocated at or near the base of the'lter, preferably having its innermostedge located about 11s inch from the base ofthe filter, as this helps toprevent the filter mass from being seen while in service. The overallheight of the nasal lter is preferably about 1%2 inch although thismaybe varied some, for instance between the Aapproximate limits of 1/8 inchand inch, dependingr upon the overall length of lthe filter and upon theresiliency of the composition used.

Filter mass IB which isv placed inside the filter, is preferably made of-coil lambswoolwhich has 4 been dipped in a solution of about 1 to 10%,depending on solubility, by weight of petrolatum in a volatile solutionsuch as a petroleum naphtha. Other slightly heavier solvent fractionsmay be used such as a refined kerosene or a varnolene fraction which isintermediate between a naphtha and a` kerosene, or other types of lessinflammable solvents such as carbon tetrachloride, or any suitable mixedsolvent. After the lambs wool has been dipped into such a solution itshould be dried, i. e. the solvent permitted to evaporate completelywhereby a thin film of petrolatum is left on each of the tiny fibres ofthe lambs wool. Other non-hardening water-insoluble adhesive materialsfree from undesirable odors or toxic vapor, may be used in place of thepetrolatum, such as a viscous nonvolatile mineral oil fraction, e. g.heavy bright stock, low melting parafn wax, some natural gums, and someslightly sticky synthetic polymers. The filter mass lil may eitherbestuffed into the filter in any irregular manner, or may be`pre-manufactured in the form of a thin pad ofl suitable thickness,which may then be cut out with a pair of scissors by the user, to t theparticular size lters to be used, or such pads may be pre-manufacturednot only in the desired thickness but in the desired shape to t lters ofthe various sizes. It is of course desirable that the lter mass fitreasonably snugly at the ends 'l `and 8 of the lter so as to preventpassage of air without being filtered.

Fig. 3 representing an end view of the lter shows that the top cornersof the inner and outer side walls 3 and 4 respectively should preferablybe rounded for ease of insertion and for comfort.

This gure also shows the lter mass retainingridge 9 which protrudesinwardly from the side walls as well as from the ends as mentionedv indescribing Fig. 2. It is also apparent in Fig. 3 that the filter massI!) should fit snugly with the side walls of the filter to preventpassage of air without ltering.

Fig. 4 shows a top view of an alternative modication of the invention inwhich the side walls 4 are both curved as in the case of the outer wallsofv the separat-e left and right filters described in Fig. 1. Thus, thefilter of' Fig. 4 is intended to be used in either the right or leftnostril and is interchangeable. The cross-hatch openings 5 are shown ashaving a more rectangular shape due to the cross bars 6 beingsubstantially at right angles to the longitudinal axis of the filter.However, it is not intended that this interchangeable shape of thenasal'lter as a lwhole be limited to the use of this particular designof cross-hatch openings and cross bars, in other words in this type ofiilter one may use the slanting type of cross bars as in Fig. 1, or theymaybemade in any other suitable designs such as curved or V shaped, etc.to provide more resiliency. The general shape illustrated in Fig. 4' maybe termed pear shaped for the sake of simplicity, while that in Fig. 1may be called pear shaped on one side and straight on the other.

Fig. 5 shows a vertical section or side view of. al suitable filter masswhichy may be pre-manufacturedin the form of a pad in which the filtermass l0 is held between a lower sheet IlI and upper sheet I2 of perviousor open-weave textile .material such as a light gauze which may or maynot, asdesired, `be actually bonded to the lambs wool with a suitableadhesive such as a gum or rubber adhesive, or a synthetic polymer ofthepolybutene type. If desired, only one of such supporting sheets maybe used, in which case it is preferably the lower one Il, the upper oneI2 being omitted.

In using the invention, it is preferable to renew the filter massfrequently enough to insure efficient removal of pollen from the airbeing inhaled 4by the user. During seasons when the air is particularlyladen with rag weed pollen and other obnoxious pollens or dusts, it maybe necessary to renew the lter mass as often as 2 or 3 times per day,but during other seasons it may not be necessary to change the filtermass more than once a day or even less frequently. It may be desirableat times to sterilize the filter, and this Vmay be done by dipping it inalcohol or in boiling Water, or it may be washed in hot soapy water, andrinsed.

It is not intended that this invention be limited specifically to thematerials and modifications which have been given merely for the sake ofillustration, but in the appended claims it is intended to claim allnovelty inherent in the invention as well as all modifications comingwithin the scope and spirit of the invention.

I claim:

1. A nasal lter made of molded, flexible, and at least substantiallyelastic, non-toxic composition, having a top having cross-hatch openingswhich are positioned at an angle of about 60 from the cross-hatch aXisof the lter, whereby a resiliency is imparted to the entire filter, bothin a cross-wise direction and in a longitudinal direction, said filteralso comprising a horizontal section substantially corresponding to theinterior contour of the human nostril, the bottom of said filter beingopen, and the top having a number of cross-hatch openings amounting toat least about 40% lof the top area of said iilter.

2. Nasal iilter made of moulded flexible elastic oil-insoluble syntheticrubber composition, having a Wall thickness of about et; inch to leinch, a substantially uniform side wall height of about 1,/8 inch toinch, a horizontal section substantially corresponding to the interiorcontour of the human nostril, the bottom of said filter being open, andthe top having a number of crosshatch openings amounting to at leastabout 40% of the top area of said lter, and said crossm hatch openingsbeing positioned at an angle of about 20 to 60 from the crosswise axisof the filter, whereby a resiliency is imparted to the entire filter,both in a crosswise direction and in a longitudinal direction.

3. Filter according to claim 2 having inside thereof a nlter masscomprising a loosely packed fibrous material composed of thin flexibleand at least substantially resilient water-insoluble .lib-res coatedwith a thin iilm of non-volatile waterinsoluble adhesive.

4. Filter according to claim 2 having a filter mass retaining ridgeprotruding from the inside walls at or near the bottom edge thereof.

5. Filter according to claim 2` having substantially pear shapedhorizontal section on the side corresponding to the outer side of thenostril, and a substantially straight edge along the side correspondingto the inner side of the nostril.

6. Filter according to claim 2 having a substantially pear shapedhorizontal section and being interchangeably adapted for use in eitherthe right or left nostril.

7 Nasal filter substantially as describe-d, made of moulded flexibleelastic vulcanized synthetic rubber composition comprising a majorproportion of oil-insoluble synthetic rubber made by polymerization ofbutadiene containing about 20 to 40% of acrylonitrile, said rubbercomposition also containing pigments and/or dyes to make the entirecomposition substantially esh colored, said lilter having asubstantially uniform side Wall height of about Tse inch, a length ofabout 18/32 to 30/32 inch depending upon its intended size for differentusers, and having a horlzontal section substantially pear shaped, atleast one side having a concaved curvature and the other side beingeither straight or with concaved curvature, the front end having anarrow curvature and back and a wide curvature, the ratio of the radiusof small arc at the front/distance between the centers of the front andback arc/radius oi large arc at back end being about .12/.65/.23, thebottom of said filter being open and the top of said lter having anumber of slantwise cross-hatch openings therein to permit ready passageof air through it during respiration, and to impart both longitudinaland crosswise resiliency to said filter, the top edges along the sidesand at the ends being rounded, and there being a filter mass retainingridge protruding from the inside surfaces of the walls at about alg inchto le inch from the bottom edge.

8. A nasal lilter assembly comprising a iilter according to claim '.7,containing therein a filter mass consisting of lambs wool coated with athin nlm of petrolatum.

CLARENCE L. MCGOVNEY.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date 2,192,093 Moore Feb. 27, 19402,274,886 Carroll Mar. 3, 1942

